Sorry to read about this.
I also changed the filter inserts a week ago and had a bit of cloudiness but that went away.
Almost certainly this is where the problem lies. Think of the filter media (filter inserts) as the fishes' life-support machine; all the beneficial bacteria reside in these that process the fishes' waste, converting the toxic ammonia to less-toxic nitrates. By changing the filter inserts, you'll have lost those beneficial bacteria and inadvertently started a fish-in cycle. You don't mention an ammonia reading but it's very likely there is ammonia presence and this is what is causing the problem.
I would strongly advise (i) getting an ammonia test kit, so that you can measure ammonia/nitrite/nitrates daily or twice-daily for the next 6 weeks or so until the cycle is complete and (ii) doing water changes each day to keep ammonia and nitrite at 0 and nitrates no higher than 20 above your tap water nitrates level - the exact proportion requiring changed may be anything from as little as 10% once a day to a couple at 50% per day but dependent on your test results. If you can also get a bottle of Tetra Safe Start, then add it to the two filters - no guarantee it will work but it has the most likelihood of any beneficial bacteria products to help the fish-in cycle that you've found yourself in.
NB. Do a water change this evening - don't wait for the test kit.In future, no need to change these filter pads - just gently squeeze them in old tank water.
Separately, in order for medication to work, make sure any carbon is removed - carbon is only ever needed after medication to get rid of the remnants of it in tank water.